I use an 21 inch iMac at home but need something for when I have to file pics on location. I'm thinking that the 13.3 is more practical because of the size and weight, the fact that it can just slip into my camera bag, etc but after talking to Apple, they explained that the 15.4 works much better for editing because it has a dedicated graphics card and the way it uses ram, it doesn't have to utilise the hard drive as much (or something like that).

Of course, it will be much nicer to edit on the bigger screen but a hassle to lug around a bigger and heavier machine, so I was just wondering what the consensus is and if anyone uses the 13.3 to edit and fines it just fine or just slow and a pain... I know it's all swings and roundabouts, horses for courses and all that but would be good to get some feedback.